CN103682971B - Method and the device of laser wavelength locking - Google Patents

Abstract

The invention provides a laser wavelength locking method and device, relates to the field of lasers, expands the range of frequency drift compensation values, and ensures the normal operation of the optical network system for WDM applications. Embodiments of the present invention include: when it is detected that the frequency drift compensation value of the output light of the laser reaches a predetermined value, scanning the boundary of the current working mode of the laser, and obtaining the center frequency of the current working mode; judging whether the center frequency of the current working mode is Corresponding to a preset frequency; when it is determined that the center frequency of the current working mode does not correspond to the preset frequency, adjust the regulating current so that the center frequency of the current working mode corresponds to the preset frequency. The invention is mainly applied in the laser wavelength locking process.

Description

Laser wavelength locking method and device

technical field

The invention relates to the field of lasers, in particular to a method and device for locking the wavelength of a laser.

Background technique

Due to the aging of the device, the output optical frequency of the laser will drift, so it is necessary to lock the wavelength of the aging laser. Wavelength tunable lasers with different working principles have different wavelength locking methods. For DS-DBR (English full name: The Digital Super-mode Distributed Bragg Reflector, Chinese full name: Digital Super-mode Distributed Bragg Reflector) and SG-DBR (English full name: Thesamplegrating Distributed Bragg Reflector, Chinese full name: Sampling Grating Distributed Bragg Reflector) principle lasers, you can The wavelength locking within the life cycle is realized by changing the phase phase current in real time.

In the process of realizing the above-mentioned prior art, the inventors found the following problems in the prior art: the range of frequency drift that can be compensated by the technical solution provided by the prior art is very small, and when the frequency drift of the laser exceeds the frequency range that can be compensated, the laser The frequency of the output light cannot be locked to the preset frequency of the current operation, which will cause the service interruption of the optical network system applied by WDM (full name in English: Wavelength Division Multiplexing, full name in Chinese: Wavelength Division Multiplexing).

Contents of the invention

Embodiments of the present invention provide a wavelength locking method and device, which can increase the compensation frequency drift range and ensure the normal service of the optical network system for WDM applications.

In order to achieve the above object, embodiments of the present invention adopt the following technical solutions:

A method for laser wavelength locking, comprising:

When it is detected that the frequency drift compensation value of the output light of the laser reaches a predetermined value, performing a boundary scan of the current working mode of the laser to obtain the center frequency of the current working mode of the laser;

judging whether the center frequency of the current working mode corresponds to a preset frequency;

When it is determined that the center frequency of the current working mode does not correspond to the preset frequency, the regulating current is adjusted so that the center frequency of the current working mode corresponds to the preset frequency.

A laser wavelength locking device, comprising:

A scanning unit, configured to perform a boundary scan of the current working mode of the laser to obtain the center frequency of the current working mode of the laser when it is detected that the frequency drift compensation value of the output light of the laser reaches a predetermined value;

a judging unit, configured to judge whether the center frequency of the current working mode acquired by the scanning unit corresponds to a preset frequency;

The adjusting unit is configured to adjust the regulating current so that the center frequency of the current working mode corresponds to the preset frequency when it is determined according to the judging unit that the center frequency of the current working mode does not correspond to the preset frequency.

In the laser wavelength locking method and device provided in the embodiments of the present invention, when it is detected that the frequency drift compensation value of the output light of the laser reaches a predetermined value, the boundary of the current working mode of the laser is scanned, and the center frequency of the current working mode is obtained; Judging whether the center frequency of the current working mode corresponds to the preset frequency; when it is determined that the center frequency of the current working mode does not correspond to the preset frequency, adjusting the regulating current so that the center frequency of the current working mode corresponds to the preset frequency. In the prior art solution, when it is detected that the frequency drift of the laser exceeds a predetermined value, the frequency of the laser output light cannot be locked to the preset frequency, which will cause service interruption of the optical network system for WDM applications. The technical solution provided by the invention expands the range of the frequency drift compensation value, and locks the frequency of the output light to a preset frequency, thereby ensuring the normal service of the optical network system for WDM applications.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

FIG. 1 is a flow chart of a laser wavelength locking method in Embodiment 1 of the present invention;

2 is a flowchart of another laser wavelength locking method in Embodiment 1 of the present invention;

3 is a flowchart of a laser wavelength locking method in Embodiment 2 of the present invention;

4 is a flowchart of a laser wavelength locking method in Embodiment 2 of the present invention;

5 is a flowchart of another laser wavelength locking method in Embodiment 2 of the present invention;

6 is a flowchart of another laser wavelength locking method in Embodiment 2 of the present invention;

7 is a flow chart of another laser wavelength locking method in Embodiment 2 of the present invention;

8 is a block diagram of a laser wavelength locking device in Embodiment 3 of the present invention;

9 is a block diagram of another laser wavelength locking device in Embodiment 3 of the present invention;

10 is a block diagram of another laser wavelength locking device in Embodiment 3 of the present invention;

Fig. 11 is a block diagram of a laser wavelength locking device in Embodiment 4 of the present invention.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

Example 1

An embodiment of the present invention provides a method for laser wavelength locking, as shown in Figure 1, the method includes:

101. When it is detected that the frequency drift compensation value of the output light of the laser reaches a predetermined value, perform a boundary scan of the current working mode of the laser, and obtain a center frequency of the current working mode of the laser.

It is worth noting that the frequency drift of the output light of the laser means that the frequency of the output light of the laser changes.

In addition, the predetermined value in step 101 refers to an artificially set value that does not exceed the frequency drift range that can be compensated after the laser device is aged. The working mode in step 101 refers to the corresponding relationship between the phase current and the output optical frequency of the laser. As shown in FIG. 2, the embodiment of the present invention takes the phase current as the abscissa and the laser output optical frequency as the linear correspondence as an example. After the laser is aged, when the frequency of the laser output light drifts, the working mode will also change, for example, the working mode will drift up and down or left and right, that is, the corresponding relationship between the phase current and the laser output light frequency indicates that the graph will change up and down or left and right Change. This correspondence is only one of the correspondences between the phase current and the output light frequency of the laser, which is not limited in this embodiment of the present invention.

102. Determine whether the center frequency of the current working mode corresponds to a preset frequency.

It is worth noting that the preset frequency includes but is not limited to ITU (full name in English: International Telecommunications Union, full name in Chinese: International Telecommunication Union)) frequency, that is, the laser output optical frequency value before the laser aging, the preset frequency It is set for different lasers at the factory and cannot be set manually.

103. When it is determined that the center frequency of the current working mode does not correspond to the preset frequency, adjust the regulating current so that the center frequency of the current working mode corresponds to the preset frequency.

It is worth noting that the adjustment current includes: Frontsection or BackSection current, adjusting the adjustment current can change the center frequency of the current working mode. Wherein, the center frequency of the current working mode is the current output light frequency of the laser. The center frequency of the current working mode corresponds to the preset frequency, that is, the output light frequency of the laser is locked, that is, the wavelength of the laser is locked.

In the laser wavelength locking method provided by the embodiment of the present invention, when it is detected that the frequency drift compensation value of the output light of the laser reaches a predetermined value, the boundary of the current working mode of the laser is scanned, and the center frequency of the current working mode is obtained; Whether the center frequency of the working mode corresponds to the preset frequency; when it is determined that the center frequency of the current working mode does not correspond to the preset frequency, adjust the regulating current so that the center frequency of the current working mode corresponds to the preset frequency. In the prior art solution, when it is detected that the frequency drift of the laser exceeds a predetermined value, the frequency of the laser output light cannot be locked to the preset frequency, which will cause service interruption of the optical network system for WDM applications. The technical solution provided by the invention can increase the frequency drift range of compensation, and lock the frequency of the output light to the preset frequency, thereby ensuring the normal service of the optical network system for WDM applications.

Example 2

An embodiment of the present invention provides a method for laser wavelength locking, as shown in FIG. 3 , the method includes:

201. When it is detected that the frequency drift compensation value of the output light of the laser reaches a predetermined value, perform boundary scan in the current working mode of the laser.

It is worth noting that the relevant content of the frequency shift of the laser output light and the predetermined value in step 201 is the same as that corresponding to step 101 in Embodiment 1, and will not be described in detail here.

In addition, as shown in Figure 4, specific methods for performing boundary scan include:

2011. Adjust the current phase current, and detect whether the frequency of the output light jumps during the process of adjusting the current phase current.

It is worth noting that when the phase current is adjusted, the frequency of the laser output light changes according to a certain law, wherein the certain law can be but not limited to a linear law. In addition, the mode of adjusting the phase current includes but is not limited to adjusting from small to large.

In addition, it is worth noting that whether the frequency of the output light jumps means that the frequency of the output light does not change according to a certain rule in step 2011 .

2012. Determine the boundary of the current working mode when it is detected that the frequency of the output light jumps.

It is worth noting that when the output optical frequency hops, the electrical signal also hops accordingly. As shown in FIG. 5 , the abscissa corresponding to the current value after the jump may be used, but not limited to, to represent the boundary of the current working mode.

In addition, when it is detected that the frequency of the output light does not jump, it is necessary to continue to adjust the phase current, that is, continue to perform step 2011 until the frequency of the output light jumps.

202. Perform calculation according to the acquired boundary of the current working mode to acquire the center frequency of the current working mode.

According to the corresponding relationship described in step 101, the embodiment of the present invention takes the linear corresponding relationship between the phase current and the output optical frequency of the laser as an example. Relevant content is the same as that described in step 101. It should be noted that the linear correspondence is only one of the correspondences between the phase current and the output light frequency of the laser, which is not limited in this embodiment of the present invention.

When the phase current has a linear relationship with the laser output light frequency, the center frequency of the current working mode to be obtained in this step is the laser output light frequency corresponding to the center of the linear function of the phase current and the laser output light frequency within the boundary of the current working mode.

203. Determine whether the center frequency of the current working mode corresponds to a preset frequency.

It is worth noting that the preset frequency is the same as the relevant description in step 102, and will not be described in detail here.

In addition, a specific implementation method for judging whether the center frequency of the current working mode corresponds to a preset frequency, as shown in FIG. 6 , includes:

2031. Calculate the distance between the center frequency of the current working mode and the preset frequency.

It is worth noting that the distance to be calculated in this step, as shown in Figure 7, can be expressed as the distance between point a and point b, where point a represents the center frequency point of the current working mode, and point b represents the preset frequency at the output Corresponding points on the linear relationship between optical frequency and phase current.

The method for calculating the distance between the center frequency of the current working mode and the preset frequency provided by the embodiment of the present invention is only one method for realizing distance calculation, which is not limited in the embodiment of the present invention.

2032. When the calculated distance is less than the rated value, determine that the center frequency of the current working mode corresponds to a preset frequency; when the calculated distance is greater than or equal to the rated value, determine that the current The working mode center frequency does not correspond to the preset frequency.

It is worth noting that, when the distance calculated in step 2032 is smaller than the rated value, the following step 204 does not need to be performed.

In addition, it is worth noting that under the condition that the requirements are not strict, the rated value can be understood as an effective value that the calculated distance fluctuates in a small range around 0.

204. When it is determined that the center frequency of the current working mode does not correspond to the preset frequency, adjust the regulating current so that the center frequency of the current working mode corresponds to the preset frequency.

It is worth noting that step 204 corresponds to step 103 in Embodiment 1, and the relevant content is described in the same way, and will not be described in detail here.

In addition, the implementation method of adjusting the regulation current includes:

Calculate according to the obtained distance between the center frequency of the current working mode and the preset frequency to obtain the adjustment value of the current adjustment.

It is worth noting that, according to the function ΔL=f(ΔIback) or ΔL=f(ΔIfront), the regulation current adjustment value is obtained. Here ΔL refers to the distance between the center frequency of the current working mode and the preset frequency; ΔIback refers to the BackSection current value to be adjusted according to ΔL, and f refers to the corresponding relationship between ΔL and ΔIback. Among them, the corresponding relationship between ΔL and ΔIback can be expressed, but not limited to, using the following functional relationship: ΔIback=ΔL*y; where y=k*Iback+b, where y, k, and b are constants that are not 0, and Iback is the current BackSectio current value.

It is worth noting that the steps in the embodiment of the present invention should be repeatedly executed according to the actual situation until the center frequency of the current working mode corresponds to the preset frequency.

In the laser wavelength locking method provided by the embodiment of the present invention, when it is detected that the frequency drift compensation value of the output light of the laser reaches a predetermined value, the boundary of the current working mode of the laser is scanned, and the center frequency of the current working mode is obtained; Whether the center frequency of the working mode corresponds to the preset frequency; when it is determined that the center frequency of the current working mode does not correspond to the preset frequency, adjust the regulating current so that the center frequency of the current working mode corresponds to the preset frequency. In the prior art solution, when it is detected that the frequency drift of the laser exceeds a predetermined value, the frequency of the laser output light cannot be locked to the preset frequency, which will cause service interruption of the optical network system for WDM applications. The technical solution provided by the invention can increase the frequency drift range of compensation, and lock the frequency of the output light to the preset frequency, thereby ensuring the normal service of the optical network system for WDM applications.

Example 3

An embodiment of the present invention provides a laser wavelength locking device. As shown in FIG. 8 , the device includes: a scanning unit 31 , a judging unit 32 , and an adjusting unit 33 .

The scanning unit 31 is configured to, when it is detected that the frequency drift compensation value of the output light of the laser reaches a predetermined value, perform a boundary scan of the current working mode of the laser, and acquire the center frequency of the current working mode of the laser.

The judging unit 32 is configured to judge whether the center frequency of the current working mode obtained by the scanning unit 31 corresponds to a preset frequency.

The adjusting unit 33 is configured to adjust the regulating current so that the center frequency of the current working mode corresponds to the preset frequency when it is determined according to the judging unit 32 that the center frequency of the current working mode does not correspond to the preset frequency.

Optionally, as shown in FIG. 9 , the scanning unit 31 includes: an adjustment module 311 , a detection module 312 , a determination module 313 , and an acquisition module 314 .

An adjustment module 311, configured to adjust the current phase phase current.

The detection module 312 is configured to detect whether the frequency of the output light jumps during the adjustment of the current phase current by the adjustment module 311 .

The determination module 313 is configured to determine the boundary of the current working mode when the detection module 312 detects that the frequency of the output light jumps.

The obtaining module 314 is configured to perform calculation according to the boundary of the current working mode obtained by the determining module 313, and obtain the center frequency of the current working mode.

Optionally, as shown in FIG. 10 , the judging unit 32 includes: a first calculating module 321 and a determining corresponding module 322 . The adjustment unit 33 includes: a second calculation module 331 and an adjustment module 332 .

The first calculation module 321 is configured to calculate the distance between the center frequency of the current working mode and the preset frequency.

A corresponding determination module 322, configured to determine that the center frequency of the current working mode corresponds to a preset frequency when the distance calculated by the first calculation module 321 is less than a rated value.

The determining corresponding module 322 is further configured to determine that the center frequency of the current working mode does not correspond to a preset frequency when the distance calculated by the first calculating module 321 is greater than or equal to a rated value.

The second calculation module 331 is configured to calculate the distance between the center frequency of the current working mode and the preset frequency calculated by the first calculation module 321 to obtain an adjustment current adjustment value.

The adjustment module 332 is configured to adjust the adjustment current according to the adjustment value of the adjustment current obtained by the second calculation module 331 .

The laser wavelength locking device provided by the embodiment of the present invention, when it is detected that the frequency drift compensation value of the laser output light reaches a predetermined value, scans the boundary of the current working mode of the laser, and obtains the center frequency of the current working mode; judges the current Whether the center frequency of the working mode corresponds to the preset frequency; when it is determined that the center frequency of the current working mode does not correspond to the preset frequency, adjust the regulating current so that the center frequency of the current working mode corresponds to the preset frequency. In the prior art solution, when it is detected that the frequency drift of the laser exceeds a predetermined value, the frequency of the laser output light cannot be locked to the preset frequency, which will cause service interruption of the optical network system for WDM applications. The technical solution provided by the invention can increase the frequency drift range of compensation, and lock the frequency of output light to a preset frequency, thus ensuring the normal service of the optical network system for WDM applications.

Example 4

An embodiment of the present invention provides a laser wavelength locking device. As shown in FIG. 11 , the device includes: a processor 01 and a memory 02 .

The processor 01 is configured to perform boundary scan in the current working mode of the laser when it is detected that the frequency drift compensation value of the output light of the laser reaches a predetermined value.

The memory 02 is used for storing the predetermined value of the frequency drift compensation value of the output light of the laser.

The processor 01 is configured to adjust the current phase current, and detect whether the frequency of the output light jumps during the process of adjusting the current phase current.

The processor 01 is configured to determine the boundary of the current working mode when a jump in the frequency of the output light is detected.

The memory 02 is used to store the determined boundary of the current working mode.

It is worth noting that the memory 02 stores the determined boundary of the current working mode is the same as the relevant description of step 2012 in the above-mentioned embodiment 2, that is, the memory can store the phase current value corresponding to the boundary of the current working mode at this time.

The processor 01 is configured to perform calculations according to the obtained boundary of the current working mode, and obtain the center frequency of the current working mode.

The memory 02 is used for storing the acquired center frequency of the current working mode.

The processor 01 is configured to determine whether the center frequency of the current working mode corresponds to a preset frequency.

Memory 02, used to store preset frequencies.

The processor 01 is configured to calculate the distance between the center frequency of the current working mode and the preset frequency.

The memory 02 is configured to store the calculated distance between the center frequency of the current working mode and the preset frequency.

The processor 01 is configured to determine that the center frequency of the current working mode corresponds to a preset frequency when the calculated distance is less than a rated value.

The processor 01 is further configured to, when the calculated distance is greater than or equal to a rated value, calculate according to the obtained distance between the center frequency of the current working mode and the preset frequency to obtain an adjustment value of the current adjustment.

The memory 02 is used for storing the adjustment value of the adjustment current.

The processor 01 is configured to adjust the adjustment current according to the obtained adjustment value of the adjustment current, so that the center frequency of the current working mode corresponds to the preset frequency.

The laser wavelength locking device provided by the embodiment of the present invention, when it is detected that the frequency drift compensation value of the laser output light reaches a predetermined value, scans the boundary of the current working mode of the laser, and obtains the center frequency of the current working mode; judges the current Whether the center frequency of the working mode corresponds to the preset frequency; when it is determined that the center frequency of the current working mode does not correspond to the preset frequency, adjust the regulating current so that the center frequency of the current working mode corresponds to the preset frequency. In the prior art solution, when it is detected that the frequency drift of the laser exceeds a predetermined value, the frequency of the laser output light cannot be locked to the preset frequency, which will cause service interruption of the optical network system for WDM applications. The technical solution provided by the invention can increase the frequency drift range of compensation, and lock the frequency of the output light to the preset frequency, thus ensuring the normal service of the optical network system for WDM applications.

Through the description of the above embodiments, those skilled in the art can clearly understand that the present invention can be realized by means of software plus necessary general-purpose hardware, and of course also by hardware, but in many cases the former is a better embodiment . Based on this understanding, the essence of the technical solution of the present invention or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product is stored in a readable storage medium, such as a floppy disk of a computer , a hard disk or an optical disk, etc., including several instructions for enabling a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in various embodiments of the present invention.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. Should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (8)

1. a method for laser wavelength locking, is characterized in that, comprising:

Detection laser output light frequency drift compensation value, when the drift of laser instrument output light frequency being detectedWhen offset reaches predetermined value, carry out the boundary scan of described laser instrument work at present pattern, obtain described sharpLight device work at present mode top frequency;

Judge that whether described work at present mode top frequency is corresponding to predeterminated frequency;

In the time that definite work at present mode top frequency does not have corresponding to predeterminated frequency, adjust and regulate electric current, withMake described work at present mode top frequency corresponding to described predeterminated frequency.

2. the method for laser wavelength according to claim 1 locking, is characterized in that, described in carry outThe boundary scan of described laser instrument work at present pattern, obtains described laser instrument work at present mode top frequencyComprise:

Regulate current phase place phase electric current, and detect in the described current phase place phase electric current process of adjustingWhether output light frequency there is saltus step;

In the time described output light frequency generation saltus step being detected, determine the border of work at present pattern;

Calculate according to the border of the work at present pattern getting, obtain work at present mode top frequency.

3. the method for laser wavelength locking according to claim 1 and 2, is characterized in that, described inJudge that described work at present mode top frequency, whether corresponding to predeterminated frequency, comprising:

Calculate the distance between described work at present mode top frequency and described predeterminated frequency;

In the time that the described distance calculating is less than rated value, determine described work at present mode top frequencyCorresponding to predeterminated frequency;

In the time that the described distance calculating is more than or equal to rated value, determine in described work at present patternFrequency of heart does not correspond to predeterminated frequency.

4. the method that laser wavelength locks according to claim 3, is characterized in that, described adjustment is adjustedCurrent, comprising:

Enter according to the distance between the described work at present mode top frequency calculating and described predeterminated frequencyRow calculates, adjusted electric current adjusted value;

According to described adjusting electric current adjusted value, adjust described adjusting electric current, described adjusting electric current comprises forward lightGrid Frontsection or backward grating BackSection electric current.

5. a device for laser wavelength locking, is characterized in that, comprising:

Scanning element, in the time detecting that laser instrument output light frequency drift compensation value reaches predetermined value,Carry out the boundary scan of described laser instrument work at present pattern, obtain described laser instrument work at present mode topFrequency;

Judging unit, for judging described work at present mode top frequency that described scanning element obtains whetherCorresponding to predeterminated frequency;

Adjustment unit, determines that according to described judging unit work at present mode top frequency does not have correspondence for working asIn the time of predeterminated frequency, adjust and regulate electric current, to make described work at present mode top frequency corresponding to describedPredeterminated frequency.

6. device according to claim 5, is characterized in that, described scanning element comprises

Adjustment module, for regulating current phase place phase electric current;

Detection module, for regulating described current phase place phase electric current process to detect in described adjustment moduleWhether output light frequency there is saltus step;

Determination module, when detecting described output light frequency generation saltus step, really when described detection moduleThe border of settled front mode of operation;

Acquisition module, calculates for the border of the work at present pattern that gets according to described determination module,Obtain work at present mode top frequency.

7. according to the device described in claim 5 or 6, it is characterized in that, described judging unit comprises:

The first computing module, for calculating between described work at present mode top frequency and described predeterminated frequencyDistance;

Determine respective modules, be less than rated value for the described distance calculating when described the first computing moduleTime, determine that described work at present mode top frequency is corresponding to predeterminated frequency;

Described definite respective modules, is also greater than for the described distance calculating when described the first computing moduleOr while equaling rated value, determine that described work at present mode top frequency does not correspond to predeterminated frequency.

8. device according to claim 7, is characterized in that, described adjustment unit comprises:

The second computing module, for the described work at present pattern calculating according to described the first computing moduleDistance between centre frequency and described predeterminated frequency is calculated, adjusted electric current adjusted value;

Adjusting module, adjusts institute for the described adjusting electric current adjusted value obtaining according to described the second computing moduleState adjusting electric current.